BulkAttributeRenamer + AttributeAccumulator creates single record from multiple records which are storing attributes of a feature dispersedly

How to transform this table to the following structure?
id, aaa, bbb
001, 1, 2
002, 3, 4

One possible way is to accumulate attributes grouped by id, and then to restructure the table using a Python script:
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import fmeobjects
def restructureTable(feature):
names = feature.getAttribute('_list{}.attrName')
values = feature.getAttribute('_list{}.attrValue')
for name, value in zip(names, values):
feature.setAttribute(name, value)
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It works well but is a little inefficient, because it needs a list attribute which will not be used afterward. But I didn't know better ways.
Now, I've learned a solution using the BulkAttributeRenamer with the following parameter settings:
Selected Attributes: attrValue
Action: Regular Expression Replace
Text to Find: .*
String: attrName

After renaming, I can create a table having the preferable schema by the AttributeAccumulator without creating list attributes.